Combined spark plug and coil.



3'. s. LINCOLN. COMBINED SPARK PLUG AND COIL.

AJPLIOATIOI FILED KAY 5, 1908.

945,278. Patented Jam 4,1910. I

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EDWIN S. LINCOLN, 0F BBOOKLINE, MASSACHUSETTS, ASSIGNOR TO ELECTRIC GOODS MANUFACTUBINGCOMPANY, A CORPORATION OF MAINE.

. COMBINED SPARK PLUG AND COIL.

Specification of Letters Patent.

Patented Jan. 4,1910.

Application filed May 5, 1908. Serial No. 431,025.

following is a specification.

My lnvention relates to spark producing means for exploding a gaseous charge 111 the cylinder of a hydrocarbon motor, or the like,

and consists essentially of a spark plug of usual construction but provlded with means whereby the spark coil which supplies the high tension current to said plug may be re m ovably mounted thereon, means being also provided whereby, when the spark coil is so mounted on the spark plug, the coil terminals and the plug spark points are placed in operative relation as to each other.

It has been hitherto the practice most generally adopted in electric ignition systems.

for explosive motors to install the spark coil, with the batteries by which it is energized, in any convenient location, and to lead wires from the terminals of the secondary winding of said coil to the terminals of the ignition system, which wires are ordinarily lcd .to binding posts of which one is on the spark coil, and the other is grounded on the motor trame. Inasmuch as such connecting wires -carry current .ofhigh tension, there is a much greater liability for trouble in the working of the ignition system due to leak age of current through defective insulation than would be the case were current of low tension similar to that'by which the primary coil of the spark coil is energized, carried by such wires. f w My invention is therefore designed to produce a spark plug having provision whereby the coil by which said plug is energizeddsmechanically attached thereto, provision being also made whereby the electrical connecanother coil with a minimum of manipulation; the o erative electrical relation between the p ug and coil being broken or reestablishedby the act of mechanically disconnecting or reattaching a coil to a plug.

My invention is illustrated in its preferred form in the accompanying drawings, in which s Figure l is a .plan view of my combined plug and coil, and Fig. 2 is a side elevation of the same, partly in section. Figs. 3 and 4 show details of a modification which may be embodied in my invention. Fig. is a diagrammatic view showing the electrical connections of an ignition system in which a comblnatlon plug and C011 embodylng my invention is employed.

Referring to the drawings, the spark plu I is shown in Figs. 1 and 2 as being forme with the base portion l adapted to screw into the wall of the motor cylinder. Prefer ably having a threaded engagement with the base 1 is the top portion 2. The spark points are mounted in the base portion of the plug in usual manner; one, 3, being grounded in said base, while point 4 is located at the end of a rod running substantially centrally from a point in proximity to spark point 3 to the upper portion of the top and being insulated throughout its length in any approved manner, as by the use of the porcelain bushing 5 and washers 6 of mica or the like.

-The top portionc2 of the plug is preferably tubular, the insulating washers 6 fitting inslde the same, and it is provided with a screw cover 7 adapted to close the open end of the same. The upper ortion of the rod forming the central spar point L is uninsulated, and is exposed within an inclosed space at the upper end' of the tubular top portion 2, being preferably provided with a contact washer 8 at that-point.

Laterally extending from the upper part of top portion 2 of the plug is a boss 9, located substantially axially opposite to the center of washer 8, and adapted to receive the centrally located neck 10 of a supporting frame 11 to whichvthe spark coil 12 is seecured; Preferably neck 10 and boss 9 have a threaded enga ment'as shown, and a set screw 13 is provided for clamping said neck with reference to the .boss 9.

The spark coil 12 is of customary construction', comprising the usual primary of the primary winding at 17 and 18. The

coil windings are secured to the frame 11 in any suitable manner, as by bolts 19 passing through the windings and having terminal nuts 20 bearing agalnst an end plate 21,

preferably of insulating material.

.On the terminal end plate 21 is mounted.

the vibrator assembled in operative condi tion,.and comprising the vibrating armature 22, located adjacent the endof the core I 14 and adapted to contact with the contact screw 25 adjustably mounted in the bracket 24. The terminal 18 of the primary winding is preferably secured to bracket 24,

while in electrical connection with armature 22'is a binding post 25, from which a wire- 20 leads'to one-pole of the battery, not shown in Figs. 1 and 2, by which the coil is energized. The other pole of said battery is preferably grounded on the motor frame at some convenient point not ap earing in said figures. The second terminal 17 of the primary winding is grounded on frame 11. Thus an electrical circuit is completed through the vibrator, the primar windin I the frame 11, the metallic body 0 the spar plug, and the motor frame; a timer, not shown in Figs. 1 and'2, bein employed in usual manner to permit the ow of current for energizing the said primary winding at the desired instant. If desired a condenser may be employed to increase the efficiency of the spark coil, in which case the said condenser may be wrapped around .the outside of the coil as .shown at 27, the terminals of the same, which are not shown in the drawings, being connected in around the vibrator in customary manner.

One terminal 15 of the secondary winding is grounded on. frame 11, as well as the primary terminal 17 while the other secondary terminal 16 leads to and is connected with a pin 28 which is mounted in insulating material 29 filling the neck 10 of frame 11,

short distance as shown. The amount of the projection of pin 28 from neck 10, and the diameter of the contact washer '8 are so reforcible contact with said washer 8, so as to lated that as the neck 10 is screwed intothe boss 9, the end of pin 29 will come into establish. an efiicient electrical connection therewith. In this manner the spark point 4, which is in electrical connection with washer 8, will be placed in electrical connection with the terminal 16 of the second-.

ary winding of the spark coil, while the j otherspark" point 3 will be electrically connected with the other secondary termmal 15 through the ground afforded by the frame plug.

The scheme of the electrical connections and distribution incident to the operation of my combined spark coil and plug is (ha grammatically shown in Fig. 5. In said .figure, 31 is the battery, 32 the timer, 33 the vibrator, and 34 the condenser connected around the vibrator terminals. The core of the spark coil is indicated by 35, while 36 and 37 are res ectivel the primary and the secondary win ingso the same. At 38 may be indicated the point at which the circuit from the batter is connected to the rimary winding as at the binding post 25 of Fig. 1, the circuit through theprimary winding being completed through the ground'39. Secthrough the the spark points 41 an 42. may be taken to represen he point at which the se arable contact made by brin ing the end 0 in 28 into' contact with was er 8, as shown in Figsl and 2, takes lace, thereby placing one secondary terminaf of Fig. 5 corresponding to spark point 4 of Fig. 3. In like manner 44 represents the separable contact corresponding to that established between neck 10 and boss 9 of Fig. 2 when the former is screwed into the latter; the engagement of said neck and boss operating to com lete the secondary circuit through the spar points and the round 40, corresponding to that established t rou h frame 11, neck 10, boss 9 and the body of t e spark. plug as shown in Fig. 2. At the boss completes the primary circuit through the grpund 39, whic is made up of the same with gr ound 40, with the further addition of the motor frarfie. 1

From the-construction above described it becomes possible to replace a defective coil with a minimum of time or trouble, and without necessitatin the stopping of the employed; the rocess of making such re- 26, andto loosen set screw 13, whereupon the spark coil may bebodily removed from the spark plug by simpl unscrewing the neck 10 from the boss 9. y reversing the process a new coil may be inserted into boss 9 and reconnected with wire 26. In such process of replacement it will be noticed that the termmal 16 of the secondary winding of the spark coil-is brought into operative relation with the central spark point 4 through the bringin together of the end of pin .28 and the was er 8, which results from the screwrought into operative relation with spark ondary winding 37 has its circuit completed ground 40 and the glap between I '1 e point 43 of the coil in operative relationas to the spark point 42 same time the engagement of said neck and motor, where a mu ticylinderedniotor 1s placement simp y being to disconnect wire.

ing of neck 10 into boss 9, while terminal 15 1s 11, neck 10, boss 9, and the body of the spark elements as above mentioned in connection specifically pointed out in a previous of.

this specification.

"In addition to the facility with which any coil may be replaced in a combined plug and c'oil constructed in accordance with my in" vention themanner 1n wlnch the connectlons,

between the terminal 16 and the spark oint 4 are inclosed and protected from ontsi e injury, and in which the same are insulated with reference to the other terminal of the said secondary coil and the spark point iIf connection with the same contributes to the etliciency and permanence of the ignition system. Said connections may be embodied .in conductors of large'size and high conductivity, and the same maybe readily insulated from the neck of frame 11, and from thewall of the spark plug, withwhich the secondary teri'ninal is in electrical engagement through grounding in a permanent and effective manner, as has been more specifically hereinabove described. Thus is eliminated to a large degree the liability to defective working on the part of the ignition system by reason of leakage of the high tension current due to defective insulation. At the sametime the rigid support afforded the said connections by reason of the man- E ner in which'they are mounted in the plug body and in neck 10, avoid subjecting them i to the vibration and consequent liabllity to fracture by crystallization, which is common in ignition installations of the "nsualstype. Furthermore the protection afforded through the inclosure of such connections within the plug body and neck 10 prevents their being subjected to abrasion or other injury, by

which injury tending to interrupt the ignition system may result.

In consequence therefore of my combina tion of the spark plug and coil in the man ner above descrlbed the possibility of trouble arising in the ignition system either as a resnltof the fracture ofthe secondary connections through, crystallization, or through defects originally present in the insulation of such connections" or arising as a result of use, is reduced to a minimum, and the annoyance due to eliminated. I

A modification of my invention is shown in Figs. 3 and 4, said modification involving that cause practically contact screw bracket- 55.

more especially the manner of attaching the vibrator to the coil, 60

It hasv been any experience that defects in the vibrator are in large measure responsible for the defective working of a coil and it has been my aim in the modification .hereinafter described to provide a construction in which the said vibrator is detachably secured tothe coil, so

as to'permit the same to be easily removed a nd quickly replaced, should it be deemed bolts 47 bywhich the coil is made fast to a supporting frame, not shown in Fig. 3,

.but similar in form and function to that above described in connection with Figs. 1 'and 2.

socket plates 48 and 49, made of metal or other electrically conductive material and insulated with reference to each other, and to said plates are respectively connected the wires 5.0 and 51. \Vire 50 leads to one pole of the battery by which the coil is energized, not shown in the figures, while wire 51' is one of the terminals of the primary coil the other pole of said battery, and the other terminal of the said primary being both preferably grounded on the motor frame in similar manner to that above deend 52 of the' spark coil core is adapted to In said disk 46 are located two project for a short distance through the disk 46, and to come into working relation with the armature of the vlbrator which is superimposed on the disk .46 in a manner to be presently described.

Fig. 3 shows the vibrator in its operative position on the disk, said vibrater compris mg the vibrating armature 53, and the con 'tact screw 54 adjustably mounted in the bracket all assembled in usual/operative relation upon a base 56. Projecting from the lower surface of base are pins 57 and .58, preferably formed with split and resiliently separtedeends, which are adapted to slidmgly engage within holes whlch are provided to receive the same in the s ket "plates, 48 and 49. Said pins are locatet so as to register within the holes in the socket plates, permitting-both pinsto be simultaneously slid into engagement within the said holes, the friction engagement between the pins and the sides of the holes in the socket plates serving to retain the vibrator in'its place at the end of the-spark coil. Pin

57 is electrically connected with the vibrator armature 53 and the other pm 58 with the 'When in position at the end .of coil 45 "with' pins 57 and 58 in engagement with and passing thence into pin 57 and through i the armature 53, 1 contact screw 54 and bracket 55 into pin 58. Thence it will pass meet the same from the circuit, which it is intended to control, or the act of putting a new vibrator into place with its projecting pins in engagement with the socket plates serves to electrically connect the same in operative relation with respect to' the primary winding without requiring further connection of the coil wiring thereto.

Preferably a cover is supplied which is adapted to slip over .the spark coil and vibrator so as to protect the same from dust and moisture. Such cover is however purely a matter of detail not associated with the principles of operation of my invention and is not therefore shown in the drawings nor described-in further detail.

It may furthermore be noticed that the location of the spark coil laterally with respect to the plug brings it into such proximity to the motor cylinder as to. subject it to the drying influences resulting from the heat which arises'from the motor, and thus keeping the coil free from moisture. At the same time the fact that the coil is separate from the plug with but a small area of interengaged surfaces, prevents the conduction of heat from the cylinder wall through-the plug body to the spark coil so as to raise the temperature of the same to an injurious degree, asiwould be the case if the coil were mcorporated permanently with the plug so as to form an integral part of the same.

Having described my invention what I claim and desire to secure by Letters Pat- .ent is: I 1. The combination with a spark plug having spark points, and an induction coil adapted vto energize said spark points, of interengaging means in part secured to the coil, and in part secured to the plug, said interengaging means in their engaged relationbeing adapted to mechanically support said coil laterally with respect to the plug ahd e bodying electrical connections whereby said coil is placed in operative relation with respect tosaid spark points.

2. The combination with a spark plug having spark points, and a boss in connection with the body of said plug and extending laterally with respect thereto, of an induction coil. embodying primary and secondary windings, and having secured therto a frame having a neck adapted to remoyably engage said boss; one of the terminals of said secondary Winding being in electrical connection with one spark point, in the engaged relation of the neck and the boss, by means of said frame, said boss, and the plu body, and the other secondary terminal eing in electrical connection with the other spark point, in said eugaged relation, through a conducting pin and through a conducting bar, carried in, and electrically insulated ,from, the plug body, leading to said other spark point, and with which said pin is adapted to electrically engage in-the engaged relation of said neck and said boss.

3. The combination with a spark plug embodying a top portion provided with a mounted on said plug body, and a central spark point' having a conducting bar extending longitudinally with respect to said plug body and said to portion, and eleccomprising primary and secondary windings, said coil having secured thereto aframe electrically connected with one terminal of said secondary winding and embodying a neck adapted to engage within said boss, the other secondary terminal being in kelectrical connection with a conducting pin insulated therefrom, the end of said conducting pin being adapted to bear laterally against said central conducting bar when said neck and boss are in their engaged relation. I

In testimony whereof I afiix my signature in presence of two witnesses.

. EDWIN S. LINCOLN.

lVitnesses:

. NATHAN B. DAY, .WILLIAM A. COPELAND.

carried in said neck and insulated therefrom,

xtending through said neck and electrically? laterally extending boss, a spark point trically insulated there rom, of a spark coil 

